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Novel Features (novel + feature)
Selected AbstractsORIGINAL ARTICLE: Hyperresistinemia , a Novel Feature in Systemic Infection During Human PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2010Shali Mazaki-Tovi Citation Mazaki-Tovi S, Vaisbuch E, Romero R, Kusanovic JP, Chaiworapongsa T, Kim SK, Ogge G, Yoon BH, Dong Z, Gonzalez JM, Gervasi MT, Hassan SS. Hyperresistinemia , a novel feature in systemic infection during human pregnancy. Am J Reprod Immunol 2010 Problem, Resistin, originally described as an adipokine, has emerged as a potent pro-inflammatory protein associated with both acute and chronic inflammation. Moreover, resistin has been proposed as a powerful marker of sepsis severity, as well as a predictor of survival of critically ill non-pregnant patients. The aim of this study was to determine whether pyelonephritis during pregnancy is associated with changes in maternal plasma resistin concentrations. Methods of study, This cross-sectional study included the following groups: (i) normal pregnant women (n = 85) and (ii) pregnant women with pyelonephritis (n = 40). Maternal plasma resistin concentrations were determined by ELISA. Non-parametric statistics was used for analyses. Results, (i) The median maternal plasma resistin concentration was higher in patients with pyelonephritis than in those with a normal pregnancy (P < 0.001); (ii) among patients with pyelonephritis, the median maternal resistin concentration did not differ significantly between those with and without a positive blood culture (P = 0.3); (iii) among patients with pyelonephritis who were diagnosed with systemic inflammatory response syndrome (SIRS), those who fulfilled ,3 criteria for SIRS had a significantly higher median maternal plasma resistin concentration than those who met only two criteria; and (iv) maternal WBC count positively correlated with circulating resistin concentration (r = 0.47, P = 0.02). Conclusion, Hyperresistinemia is a feature of acute pyelonephritis during pregnancy. The results of this study support the role of resistin as an acute-phase protein in the presence of bacterial infection during pregnancy. [source] Novel features of Equisetum arvense spermatozoids: insights into pteridophyte evolutionNEW PHYTOLOGIST, Issue 1 2002K. S. Renzaglia Summary ,,To characterize structural diversity within Equisetum and among pteridophytes, architectural features of the sperm cell are described here in a second subgenus of Equisetum, a divergent basal group in the fern clade. ,,Transmission electron microscopy observations of prereleased spermatozoids of Equisetum arvense were correlated with three-dimensional scanning electron microscopy images of swimming cells. ,,The mature spermatozoid completes a helix of approximately 2.5 revolutions. At the cell anterior is a complex multilayered locomotory apparatus with staggered flagella. Mitochondria (elongated,rounded) are aggregated near the locomotory apparatus and organelles extend along the cell length. The spline contains up to 300 microtubules and wraps in part around the long cylindrical nucleus. In swimming sperm cells, the anterior of the cell remains tightly coiled while the posterior relaxes and extends in a trailing fashion. ,,Spermatozoids of Equisetum arvense are smaller than those of Equisetum hyemale but structurally similar, except for nuclear shape. Conservation of cellular features suggests recent radiation of the genus. Equisetum spermatozoids share several critical features with ferns, including Psilotum, and support monophyly of a fern,Equisetum assemblage. Entry of the male gametes of Equisetum in their entirety into the archegonial venters indicates possible biparental inheritance of chloroplast and mitochondrial genomes. [source] The parametrization of drag induced by stratified flow over anisotropic orographyTHE QUARTERLY JOURNAL OF THE ROYAL METEOROLOGICAL SOCIETY, Issue 568 2000J. F. Scinocca Abstract A new parametrization of drag arising from the flow over unresolved topography (UT) in a general-circulation model (GCM) is presented. It is comprised of three principle components: a parametrization of the source spectrum and drag associated with freely propagating hydrostatic gravity waves in the absence of rotation, a parametrization of the drag associated with low-level wave breaking, and a parametrization of low-level drag associated with upstream blocking and lee-vortex dynamics. Novel features of the scheme include: a new procedure for defining the UT in each GCM grid cell which takes account of the GCM resolution and includes only the scales represented by the parametrization scheme, a new method of representing the azimuthal distribution of vertical momentum flux by two waves whose direction and magnitude systematically vary with the flow direction and with the anisotropy of the UT in each GCM grid cell, and a new application of form drag in the lowest levels which can change the direction of the low-level flow so that it is more parallel to unresolved two-dimensional topographic ridges. The new scheme is tested in the Canadian Centre for Climate Modelling and Analysis third generation atmospheric GCM at horizontal resolutions of T47 and T63. Five-year seasonal means of present-day climate show that the new scheme improves mean sea level pressures (or mass distribution) and improves the tropospheric circulation when compared with the gravity-wave drag scheme used currently in the GCM. The benefits are most pronounced during northern hemisphere winter. It is also found that representing the azimuthal distribution of the momentum flux of the freely propagating gravity-wave field with two waves rather than just one allows 30-50% more gravity-wave momentum flux up into the middle atmosphere, depending on the season. The additional momentum flux into the middle atmosphere is expected to have a beneficial impact on GCMs that employ a more realistic representation of the stratosphere. [source] Emergency Department Information System Adoption in the United StatesACADEMIC EMERGENCY MEDICINE, Issue 5 2010Adam B. Landman MD Abstract Objectives:, The American Recovery and Reinvestment Act of 2009 incentivizes adoption of health care information technology (HIT) based on support for specific standards, policies, and features. Limited data have been published on national emergency department information systems (EDIS) adoption, and to our knowledge, no prior studies have considered functionality measures. This study determined current national estimates of EDIS adoption using both single-response rates of EDIS adoption and a novel feature-based definition and also identified emergency department (ED) characteristics associated with EDIS use. Methods:, The 2006 National Hospital Ambulatory Medical Care Survey, a nationally representative sample of ED visits that also surveyed participating EDs on EDIS, was used to estimate EDIS adoption. EDIS adoption rates were calculated using two definitions: 1) single-response,response to a single survey question as to whether the EDIS was complete, partial, or none; and 2) feature-based,based on the reported features supported by the EDIS, systems were categorized as fully functional, basic, other, or none. The relationship of EDIS adoption to specific ED characteristics such as facility type and location was also examined. Results:, Using the single-response classification, 16.1% of EDs had a complete EDIS, while 30.4% had a partial EDIS, and 53.5% had none. In contrast, using a feature-based categorization, 1.7% EDs had a fully functional EDIS, 12.3% had basic, 32.1% had other, and 53.9% had none. In multivariable analysis, urban EDs were significantly more likely to have a fully functional or basic EDIS than were rural EDs. Pediatric EDs were significantly more likely than general EDs to have other EDIS. Conclusions:, Despite more optimistic single-response estimates, fewer than 2% of our nation's EDs have a fully functional EDIS. EDs in urban areas and those specializing in the care of pediatric patients are more likely to support EDIS. Accurate and consistent EDIS adoption estimates are dependent on whether there are standardized EDIS definitions and classifications of features. To realize the potential value of EDIS for improved emergency care, we need to better understand the extent and correlates of the diffusion of this technology and increase emergency medicine engagement in national HIT policy-making. Academic Emergency Medicine 2010; 17:536,544 © 2010 by the Society for Academic Emergency Medicine [source] Expression of Hoxa-11 and Hoxa-13 in the pectoral fin of a basal ray-finned fish, Polyodon spathula: implications for the origin of tetrapod limbsEVOLUTION AND DEVELOPMENT, Issue 3 2005Brian D. Metscher Summary Paleontological and anatomical evidence suggests that the autopodium (hand or foot) is a novel feature that distinguishes limbs from fins, while the upper and lower limb (stylopod and zeugopod) are homologous to parts of the sarcopterygian paired fins. In tetrapod limb development Hoxa-11 plays a key role in differentiating the lower limb and Hoxa-13 plays a key role in differentiating the autopodium. It is thus important to determine the ancestral functions of these genes in order to understand the developmental genetic changes that led to the origin of the tetrapod autopodium. In particular it is important to understand which features of gene expression are derived in tetrapods and which are ancestral in bony fishes. To address these questions we cloned and sequenced the Hoxa-11 and Hoxa-13 genes from the North American paddlefish, Polyodon spathula, a basal ray-finned fish that has a pectoral fin morphology resembling that of primitive bony fishes ancestral to the tetrapod lineage. Sequence analysis of these genes shows that they are not orthologous to the duplicated zebrafish and fugu genes. This implies that the paddlefish has not duplicated its HoxA cluster, unlike zebrafish and fugu. The expression of Hoxa-11 and Hoxa-13 in the pectoral fins shows two main phases: an early phase in which Hoxa-11 is expressed proximally and Hoxa-13 is expressed distally, and a later phase in which Hoxa-11 and Hoxa-13 broadly overlap in the distal mesenchyme of the fin bud but are absent in the proximal fin bud. Hence the distal polarity of Hoxa-13 expression seen in tetrapods is likely to be an ancestral feature of paired appendage development. The main difference in HoxA gene expression between fin and limb development is that in tetrapods (with the exception of newts) Hoxa-11 expression is suppressed by Hoxa-13 in the distal limb bud mesenchyme. There is, however, a short period of limb bud development where Hoxa-11 and Hoxa-13 overlap similarly to the late expression seen in zebrafish and paddlefish. We conclude that the early expression pattern in tetrapods is similar to that seen in late fin development and that the local exclusion by Hoxa-13 of Hoxa-11 from the distal limb bud is a derived feature of limb developmental regulation. [source] A semiparametric model for binary response and continuous outcomes under index heteroscedasticityJOURNAL OF APPLIED ECONOMETRICS, Issue 5 2009Roger Klein This paper formulates a likelihood-based estimator for a double-index, semiparametric binary response equation. A novel feature of this estimator is that it is based on density estimation under local smoothing. While the proofs differ from those based on alternative density estimators, the finite sample performance of the estimator is significantly improved. As binary responses often appear as endogenous regressors in continuous outcome equations, we also develop an optimal instrumental variables estimator in this context. For this purpose, we specialize the double-index model for binary response to one with heteroscedasticity that depends on an index different from that underlying the ,mean response'. We show that such (multiplicative) heteroscedasticity, whose form is not parametrically specified, effectively induces exclusion restrictions on the outcomes equation. The estimator developed exploits such identifying information. We provide simulation evidence on the favorable performance of the estimators and illustrate their use through an empirical application on the determinants, and affect, of attendance at a government-financed school. Copyright © 2009 John Wiley & Sons, Ltd. [source] Unemployment and liquidity constraintsJOURNAL OF APPLIED ECONOMETRICS, Issue 3 2007Vassilis A. Hajivassiliou We present a dynamic framework for the interaction between borrowing (liquidity) constraints and deviations of actual hours from desired hours, both measured by discrete-valued indicators, and estimate it as a system of dynamic binary and ordered probit models with panel data from the Panel Study of Income Dynamics. We analyze a household's propensity to be liquidity constrained by means of a dynamic binary probit model. We analyze qualitative aspects of the conditions of employment, namely whether the household head is involuntarily overemployed, voluntarily employed, or involuntarily underemployed or unemployed, by means of a dynamic ordered probit model. We focus on the possible interaction between the two types of constraints. We estimate these models jointly using maximum simulated likelihood, where we allow for individual random effects along with an autoregressive process for the general error term in each equation. A novel feature of our method is that it allows for the random effects to be correlated with regressors in a time-invariant fashion. Our results provide strong support for the basic theory of constrained behavior and the interaction between liquidity constraints and exogenous constraints on labor supply. Copyright © 2007 John Wiley & Sons, Ltd. [source] Quinolinic acid modulates the activity of src family kinases in rat striatum: in vivo and in vitro studiesJOURNAL OF NEUROCHEMISTRY, Issue 5 2006Alessio Metere Abstract Quinolinic acid (QA) has been shown to evoke neurotoxic events via NMDA receptor (NMDAR) overactivation and oxidative stress. NMDARs are particularly vulnerable to free radicals, which can modulate protein tyrosine kinase (PTK) and phosphotyrosine phosphatase (PTP) activities. The src family of tyrosine kinases are associated with the NMDAR complex and regulate NMDA channel function. Because QA is an NMDAR agonist as well as a pro-oxidant agent, we investigated whether it may affect the activity of PTKs and PTPs in vivo and in vitro. In synaptosomes prepared from striata dissected 15 min, 30 min or 15 days after bilateral injection of QA we observed modulation of the phosphotyrosine pattern; a significant decrease in PTP activity; and a sustained increase in c-src and lyn activity at 15 and 30 min after treatment with QA, followed by a decrease 2 weeks later. Striatal synaptosomes treated in vitro with QA showed time- and dose-dependent modulation of c-src and lyn kinase activities. Moreover, the nitric oxide synthase inhibitor NG -nitro- l -arginine-methyl ester, the NMDAR antagonist d -2-amino-5-phosphonovaleric acid and pyruvate suppressed the QA-induced modulation of c-src activity. These findings suggest a novel feature of QA in regulating src kinase activity through the formation of reactive radical species and/or NMDAR overactivation. [source] Dynamic update of Java applications,balancing change flexibility vs programming transparencyJOURNAL OF SOFTWARE MAINTENANCE AND EVOLUTION: RESEARCH AND PRACTICE, Issue 2 2009Allan Raundahl Gregersen Abstract The ability to dynamically change the behavior of an application is becoming an important issue in contemporary rich client software development. Not only can programmers benefit from dynamic updates during the development of concurrent applications where recreation of complex application states can be avoided during test and debugging but also at post-deployment time where applications can be updated transparently without going through the well-known halt, redeploy and restart scheme. In this paper, we explain how our dynamic update framework achieves transparent dynamic updates of running Java applications while guaranteeing both type and thread safety. A novel feature of our approach is that it supports full redefinition of classes by allowing changes to the type hierarchy. Our approach is based on a lightweight runtime system, which is injected into an application via bytecode transformations at class loading. We show how our approach can add dynamic update capabilities to rich client development by integrating it with the NetBeans rich client platform. Performance experiments on our NetBeans implementation show that the overhead of our approach is low when applied to component application programming interface classes. To the best of our knowledge no other existing approach achieves the same level of low overhead and programming transparency. Copyright © 2009 John Wiley & Sons, Ltd. [source] The Aspergillus nidulans sldIRAD50 gene interacts with bimEAPC1, a homologue of an anaphase-promoting complex subunitMOLECULAR MICROBIOLOGY, Issue 1 2005Iran Malavazi Summary The Mre11,Rad50,Nbs1 protein complex has emerged as a central component in the human cellular DNA damage response, and recent observations suggest that these proteins are at least partially responsible for the linking of DNA damage detection to DNA repair and cell cycle checkpoint functions. We have identified Aspergillus nidulans sldI1444D mutant in a screen for dynein synthetic lethals. The sldIRAD50 gene was cloned by complementation of the sporulation deficiency phenotype of this mutant. A transversion G,C at the position 2509 (Ala-692-Pro amino acid change) in the sldI1444D mutant causes sensitivity to several DNA-damaging agents. The mutation sldI1 occurs at the CXXC hinge domain of Rad50. We have deleted part of the coiled-coil and few amino acids of the Rad50,Mre11 interaction region and assessed several phenotypic traits in this deletion strain. Besides sensitivity to a number of DNA-damaging agents, this deletion strain is also impaired in the DNA replication checkpoint response, and in ascospore viability. There is no delay of the S-phase when germlings of both sldI RAD50 and mreAMRE11 inactivation strains were exposed to the DNA damage caused by bleomycin. Transformation experiments and Southern blot analysis indicate homologous recombination is dependent on scaANBS1 function in the Mre11 complex. There are epistatic and synergistic interactions between sldI RAD50 and bimEAPC1 at S-phase checkpoints and response to hydroxyurea and UV light. Our results suggest a possible novel feature of the Mre11 complex in A. nidulans, i.e. a relationship with bimE,APC1. [source] Interaction of UV Radiation and Inorganic Carbon Supply in the Inhibition of Photosynthesis: Spectral and Temporal Responses of Two Marine Picoplankters,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 2 2005Cristina Sobrino ABSTRACT The effect of ultraviolet radiation (UVR) on inhibition of photosynthesis was studied in two species of marine picoplankton with different carbon concentration mechanisms: Nannochloropsis gaditana Lubián possesses a bicarbonate uptake system and Nannochloris atomus Butcher a CO2 active transport system. Biological weighting functions (BWFs) for inhibition of photosynthesis by UVR and photosynthesis vs irradiance (PI) curves for photosynthetically active radiation (PAR) were estimated for both species grown with an enriched CO2 supply (high dissolved inorganic carbon [DIC]: 1% CO2 in air) and in atmospheric CO2 levels (low DIC: 0.03% CO2). The response to UVR and PAR exposures was different in each species depending on the DIC treatment. Under PAR exposure, rates of maximum photosynthesis were similar between treatments in N. gaditana. However, the cultures growing in high DIC had lower sensitivity to UVR than the low DIC cultures. In contrast, N. atomus had higher rates of photosynthesis under PAR exposure with high DIC, but the BWFs were not significantly different between treatments. The results suggest that one or more processes in N. gaditana associated with HCO3, transport are target(s) for UV photodamage because there was relatively less UV inhibition of the high DIC-grown cultures in which inorganic carbon fixation is supplied by passive CO2 diffusion. Time courses of photochemical efficiency in PAR, during UV exposure and during subsequent recovery in PAR, were determined using a pulse amplitude modulated fluorometer. The results were consistent with the BWFs. In all time courses, a steady state was obtained after an initial decrease, consistent with a dynamic balance between damage and repair as found for other phytoplankton. However, the relationship of response to exposure showed a steep decline in activity that is consistent with a constant rate of repair. A novel feature of a model developed from a constant repair rate is an explicit threshold for photosynthetic response to UV. [source] ORIGINAL ARTICLE: Hyperresistinemia , a Novel Feature in Systemic Infection During Human PregnancyAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2010Shali Mazaki-Tovi Citation Mazaki-Tovi S, Vaisbuch E, Romero R, Kusanovic JP, Chaiworapongsa T, Kim SK, Ogge G, Yoon BH, Dong Z, Gonzalez JM, Gervasi MT, Hassan SS. Hyperresistinemia , a novel feature in systemic infection during human pregnancy. Am J Reprod Immunol 2010 Problem, Resistin, originally described as an adipokine, has emerged as a potent pro-inflammatory protein associated with both acute and chronic inflammation. Moreover, resistin has been proposed as a powerful marker of sepsis severity, as well as a predictor of survival of critically ill non-pregnant patients. The aim of this study was to determine whether pyelonephritis during pregnancy is associated with changes in maternal plasma resistin concentrations. Methods of study, This cross-sectional study included the following groups: (i) normal pregnant women (n = 85) and (ii) pregnant women with pyelonephritis (n = 40). Maternal plasma resistin concentrations were determined by ELISA. Non-parametric statistics was used for analyses. Results, (i) The median maternal plasma resistin concentration was higher in patients with pyelonephritis than in those with a normal pregnancy (P < 0.001); (ii) among patients with pyelonephritis, the median maternal resistin concentration did not differ significantly between those with and without a positive blood culture (P = 0.3); (iii) among patients with pyelonephritis who were diagnosed with systemic inflammatory response syndrome (SIRS), those who fulfilled ,3 criteria for SIRS had a significantly higher median maternal plasma resistin concentration than those who met only two criteria; and (iv) maternal WBC count positively correlated with circulating resistin concentration (r = 0.47, P = 0.02). Conclusion, Hyperresistinemia is a feature of acute pyelonephritis during pregnancy. The results of this study support the role of resistin as an acute-phase protein in the presence of bacterial infection during pregnancy. [source] 12-Membered borophosphate rings in KNi5[P6B6O23(OH)13]ACTA CRYSTALLOGRAPHICA SECTION C, Issue 12 2009Olga V. Yakubovich The title compound, potassium pentanickel hexaborophosphate tridecahydroxide, was synthesized under hydrothermal conditions from the NiCl2,K3PO4,B2O3,K2CO3,H2O system. The crystal structure was determined using single-crystal X-ray diffraction at 100,K. The KNi5[P6B6O23(OH)13] phase is cubic. For the three crystallographically distinct Ni centers, two occupy sites with 3 symmetry, while the third Ni and the K atom are located on sites. The structure is built from alternating borate and phosphate tetrahedra forming 12-membered puckered rings with K+ ions at the centers. These rings are arranged as in cubic dense sphere packing. A novel feature of the new crystal structure is the presence of linear trimers of face-sharing [NiO6] octahedra occupying the octahedral interstices of this sphere packing, and of single [NiO6] octahedra in the tetrahedral interstices. All oxygen corners of the Ni octahedra are linked to phosphate or borate tetrahedra of the 12-membered rings to form a mixed anionic framework. [source] The structure of the genomic Bacillus subtilis dUTPase: novel features in the Phe-lidACTA CRYSTALLOGRAPHICA SECTION D, Issue 9 2010Javier García-Nafría dUTPases are a ubiquitous family of enzymes that are essential for all organisms and catalyse the breakdown of 2-deoxyuridine triphosphate (dUTP). In Bacillus subtilis there are two homotrimeric dUTPases: a genomic and a prophage form. Here, the structures of the genomic dUTPase and of its complex with the substrate analogue dUpNHpp and calcium are described, both at 1.85,Å resolution. The overall fold resembles that of previously solved trimeric dUTPases. The C-terminus, which contains one of the conserved sequence motifs, is disordered in both structures. The crystal of the complex contains six independent protomers which accommodate six dUpNHpp molecules, with three triphosphates in the trans conformation and the other three in the active gauche conformation. The structure of the complex confirms the role of several key residues that are involved in ligand binding and the position of the catalytic water. Asp82, which has previously been proposed to act as a general base, points away from the active site. In the complex Ser64 reorients in order to hydrogen bond the phosphate chain of the substrate. A novel feature has been identified: the position in the sequence of the `Phe-lid', which packs against the uracil moiety, is adjacent to motif III, whereas in all other dUTPase structures the lid is in a conserved position in motif V of the flexible C-terminal arm. This requires a reconsideration of some aspects of the accepted mechanism. [source] Mixture Modeling for Genome-Wide Localization of Transcription FactorsBIOMETRICS, Issue 1 2007Sündüz Kele Summary Chromatin immunoprecipitation followed by DNA microarray analysis (ChIP-chip methodology) is an efficient way of mapping genome-wide protein,DNA interactions. Data from tiling arrays encompass DNA,protein interaction measurements on thousands or millions of short oligonucleotides (probes) tiling a whole chromosome or genome. We propose a new model-based method for analyzing ChIP-chip data. The proposed model is motivated by the widely used two-component multinomial mixture model of de novo motif finding. It utilizes a hierarchical gamma mixture model of binding intensities while incorporating inherent spatial structure of the data. In this model, genomic regions belong to either one of the following two general groups: regions with a local protein,DNA interaction (peak) and regions lacking this interaction. Individual probes within a genomic region are allowed to have different localization rates accommodating different binding affinities. A novel feature of this model is the incorporation of a distribution for the peak size derived from the experimental design and parameters. This leads to the relaxation of the fixed peak size assumption that is commonly employed when computing a test statistic for these types of spatial data. Simulation studies and a real data application demonstrate good operating characteristics of the method including high sensitivity with small sample sizes when compared to available alternative methods. [source] The Low-Lying Excited States of 2,2,-Bithiophene: A Theoretical AnalysisCHEMPHYSCHEM, Issue 12 2003Mercedes Rubio Dr. Abstract The low-energy regions of the singlet,singlet, singlet,triplet, and triplet,triplet electronic spectra of 2,2,-bithiophene are studied using multiconfigurational second-order perturbation theory (CASPT2) and extended atomic natural orbitals (ANO) basis sets. The computed vertical, adiabatic, and emission transition energies are in agreement with the available experimental data. The two lowest singlet excited states, 11Bu and 21Bu, are computed to be degenerate, a novel feature of the system to be borne in mind during the rationalization of its photophysics. As regards the observed high triplet quantum yield of the molecule, it is concluded that the triplet states 23Ag and 23Bu, separated about 0.4 eV from the two lowest singlet excited states, can be populated by intersystem crossing from nonplanar singlet states. [source] SORTAL ANAPHORA RESOLUTION IN MEDLINE ABSTRACTSCOMPUTATIONAL INTELLIGENCE, Issue 1 2007Manabu Torii This paper reports our investigation of machine learning methods applied to anaphora resolution for biology texts, particularly paper abstracts. Our primary concern is the investigation of features and their combinations for effective anaphora resolution. In this paper, we focus on the resolution of demonstrative phrases and definite determiner phrases, the two most prevalent forms of anaphoric expressions that we find in biology research articles. Different resolution models are developed for demonstrative and definite determiner phrases. Our work shows that models may be optimized differently for each of the phrase types. Also, because a significant number of definite determiner phrases are not anaphoric, we induce a model to detect anaphoricity, i.e., a model that classifies phrases as either anaphoric or nonanaphoric. We propose several novel features that we call highlighting features, and consider their utility particularly for processing paper abstracts. The system using the highlighting features achieved accuracies of 78% and 71% for demonstrative phrases and definite determiner phrases, respectively. The use of the highlighting features reduced the error rate by about 10%. [source] Spermatogenesis in Boccardiella hamata (Polychaeta: Spionidae) from the Sea of Japan: sperm formation mechanisms as characteristics for future taxonomic revisionACTA ZOOLOGICA, Issue 4 2010Arkadiy A. Reunov Abstract Reunov, A.A., Yurchenko, O.V., Alexandrova, Y.N. and Radashevsky, V.I. 2009. Spermatogenesis in Boccardiella hamata (Polychaeta: Spionidae) from the Sea of Japan: sperm formation mechanisms as characteristics for future taxonomic revision. ,Acta Zoologica (Stockholm) 91: 477,456. To characterize novel features that will be useful in the discussion and validation of the spionid polychaete Boccardiella hamata from the Sea of Japan, the successive stages of spermatogenesis were described and illustrated. Spermatogonia, spermatocytes and early spermatids are aflagellar cells that develop synchronously in clusters united by a cytophore. At the middle spermatid stage, the clusters undergo disintegration and spermatids produce flagella and float separately in coelomic fluid as they transform into sperm. Spermatozoa are filiform. The ring-shaped storage platelets are located along the anterior nuclear area. The nucleus is cupped by a conical acrosome. A nuclear plate is present between the acrosome and nucleus. The nucleus is a cylinder with the implantation fossa throughout its length and with the anterior part of the flagellum inside the fossa. There is only one centriole, serving as a basal body of the flagellum, situated in close vicinity of the acrosomal area. A collar of four mitochondria is located under the nuclear base. The ultrastructure of B. hamata spermatozoa from the Sea of Japan appears to be close to that of B. hamata from Florida described by Rice (Microscopic Anatomy of Invertebrates, Wiley-Liss, Inc., New York, 1992), suggesting species identity of the samples from the two regions. However, more detailed study of Florida's B. hamata sperm is required for a reliable conclusion concerning the similarity of these two polychaetes. In addition to sperm structure, features such as the cytophore-assigned pattern of spermatogenic cell development, the synchronous pattern of cell divisions, the non-flagellate early spermatogenic stages, and the vesicle amalgamation that drives meiotic cell cytokinesis and spermatid diorthosis will likely be useful in future testing of the validity of B. hamata and sibling species throughout the world. [source] Microevolution in agricultural environments: how a traditional Amerindian farming practice favours heterozygosity in cassava (Manihot esculenta Crantz, Euphorbiaceae)ECOLOGY LETTERS, Issue 2 2005Benoît Pujol Abstract We demonstrate a novel case of selection for heterozygosity in nature, involving inadvertent human selection on a population of domesticated plants. Amerindian farmers propagate cassava (Manihot esculenta) clonally by cuttings. Seedlings also appear spontaneously in fields, and farmers allow them to grow, later using some for cuttings. These ,volunteers' contribute new genotypes. However, many are inbred, whereas multiplied clones are highly heterozygous. We demonstrate the selective retention of heterozygous volunteers. When farmers weeded fields, they killed small volunteers, but retained large ones. Plant size and heterozygosity were correlated, and both increased after weeding. The process we document allows maintenance of genotypically diverse and heterozygous clonal stocks. Demonstrating heterosis in nature usually requires large sample sizes, but novel features of our system allowed escape of this constraint. Traditional agroecosystems offer unusual opportunities for the microevolutionary studies required to give on-farm conservation of genetic resources a solid scientific basis. [source] CD30 ligation differentially affects CXCR4-dependent HIV-1 replication and soluble CD30 secretion in non-Hodgkin cell lines and in ,,,,T,lymphocytesEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 11 2003Priscilla Biswas Abstract We studied whether signaling through CD30, a member of the TNF receptor family, affected acute infection with HIV-1, encompassing its entire replicative cycle. Several non-Hodgkin cell lines, targets of CXCR4-dependent (X4) HIV-1 infection, were positive for CD30 expression. CD30 ligation induced up-regulation of viral replication only in certain CD30+ cell lines. Enhancement ofX4 virus replication by CD30 engagement inversely correlated with both CD30 surface density and constitutive NF-,B activation. Conversely, expression of CD30, but not of other members of the TNF receptor family, was proportional to constitutive NF-,B binding. Concomitantly, secretion of soluble (s) CD30 increased in all cell lines by CD30 ligation. sCD30 release was enhanced by engagement of CD30 alone and, to a greater extent, by co-engagement of CD3 also in primary ,,,,T,lymphocytes, along with complementary modulations of their surface CD30 expression. sCD30-containing supernatant specifically inhibited HIV-1 expression induced by CD30 engagement in chronically infected ACH-2 T,cells; thus sCD30 may act as a negative feed-back molecule. In conclusion, we have delineated novel features of CD30 biology and underline the peculiar link of CD30 expression to constitutive NF-,B activation which is pivotal to both HIV replication and cell survival. [source] Beetle horns are regulated by the Hox gene, Sex combs reduced, in a species- and sex-specific mannerEVOLUTION AND DEVELOPMENT, Issue 4 2010Bethany R. Wasik SUMMARY Discovering the mechanisms that underlie the origin of novel features represents a major frontier in developmental and evolutionary biology. Here we begin to characterize the role of the Hox gene Sex combs reduced (Scr) during the development and evolution of a morphologically novel trait: beetle horns. Beetle horns develop as epidermal outgrowths from the prothorax and/or head, and size and location vary dramatically across species and between sexes. Using both comparative gene expression and larval RNA interference in two species of the horned beetle genus Onthophagus, we show that Scr functions in patterning adult labial mouthpart identity and suppressing wing development in the prothorax. At the same time, however, our results illustrate that Scr has acquired, within its ancestral domain of expression, additional new functions including the regulation of prepupal growth and pupal remodeling of pronotal horn primordia. Furthermore, comparative analyses of our results across both Onthophagus species, which differ in location of horn development (thoracic horns vs. thoracic and head horns) as well as patterns of sexual dimorphism (traditional vs. reversed sexual dimorphism), reveal surprising differences in exactly when, where, and to what degree Scr regulates horn formation in different sexes. These observations suggest that the interactions between Scr and its targets in the regulation of horn development can diversify quickly over remarkably short phylogenetic distances. More generally, our results suggest that the Hox complex can play an integral role in the development and evolution of novel complex traits while maintaining traditional patterning responsibilities. [source] Integrated Multifunctional Nanosystems for Medical Diagnosis and TreatmentADVANCED FUNCTIONAL MATERIALS, Issue 21 2009*Article first published online: 9 OCT 200, Donglu Shi Abstract This article provides an overview on the development of integrated multifunctional nanosystems for medical diagnosis and treatment. In particular, a novel system is developed specifically for achieving simultaneous diagnosis and treatment of cancer. Critical issues are addressed on the architecture and assembly of nanocomponents based on medical requirements: targeted in vivo imaging, controlled drug release, localized hyperthermia, and toxicity. Nanotube-based carriers are summarized with surface functionalized properties. Other types of nanocarriers are also included such as super paramagnetic composite nanospheres and biodegradable hydroxylapatite nanoparticles. In addition, polymeric-based nanosystems are introduced with several novel features: they can be bio-dissolved due to environmental pH and temperature fluctuations. The nanocarriers are surface tailored with key functionalities: surface antibodies for cell targeting, anti-cancer drug loading, and magnetic nanoparticles for both hyperthermia and MRI. Future requirements, aims, and trends in the development of multifunctional nanosystems, particularly with intelligent functionalities for fundamental studies, are also provided. [source] Modeling Age Differences in Infant Category LearningINFANCY, Issue 2 2004Thomas R. Shultz We used an encoder version of cascade correlation to simulate Younger and Cohen's (1983, 1986) finding that 10-month-olds recover attention on the basis of correlations among stimulus features, but 4- and 7-month-olds recover attention on the basis of stimulus features. We captured these effects by varying the score threshold parameter in cascade correlation, which controls how deeply training patterns are learned. When networks learned deeply, they showed more error to uncorrelated than to correlated test patterns, indicating that they abstracted correlations during familiarization. When prevented from learning deeply, networks decreased error during familiarization and showed as much error to correlated as to uncorrelated tests but less than to test items with novel features, indicating that they learned features but not correlations among features. Our explanation is that older infants learn more from the same exposure than do younger infants. Unlike previous explanations that postulate unspecified qualitative shifts in processing with age, our explanation focuses on quantitatively deeper learning with increasing age. Finally, we provide some new empirical evidence to support this explanation. [source] P-wave and S-wave decomposition in boundary integral equation for plane elastodynamic problemsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 12 2003Emmanuel Perrey-Debain Abstract The method of plane wave basis functions, a subset of the method of Partition of Unity, has previously been applied successfully to finite element and boundary element models for the Helmholtz equation. In this paper we describe the extension of the method to problems of scattering of elastic waves. This problem is more complicated for two reasons. First, the governing equation is now a vector equation and second multiple wave speeds are present, for any given frequency. The formulation has therefore a number of novel features. A full development of the necessary theory is given. Results are presented for some classical problems in the scattering of elastic waves. They demonstrate the same features as those previously obtained for the Helmholtz equation, namely that for a given level of error far fewer degrees of freedom are required in the system matrix. The use of the plane wave basis promises to yield a considerable increase in efficiency over conventional boundary element formulations in elastodynamics. Copyright © 2003 John Wiley & Sons, Ltd. [source] Quantitative X-ray projection microscopy: phase-contrast and multi-spectral imagingJOURNAL OF MICROSCOPY, Issue 2 2002S. C. Mayo Summary We outline a new approach to X-ray projection microscopy in a scanning electron microscope (SEM), which exploits phase contrast to boost the quality and information content of images. These developments have been made possible by the combination of a high-brightness field-emission gun (FEG)-based SEM, direct detection CCD technology and new phase retrieval algorithms. Using this approach we have been able to obtain spatial resolution of < 0.2 µm and have demonstrated novel features such as: (i) phase-contrast enhanced visibility of high spatial frequency image features (e.g. edges and boundaries) over a wide energy range; (ii) energy-resolved imaging to simultaneously produce multiple quasi-monochromatic images using broad-band polychromatic illumination; (iii) easy implementation of microtomography; (iv) rapid and robust phase/amplitude-retrieval algorithms to enable new real-time and quantitative modes of microscopic imaging. These algorithms can also be applied successfully to recover object,plane information from intermediate-field images, unlocking the potentially greater contrast and resolution of the intermediate-field regime. Widespread applications are envisaged for fields such as materials science, biological and biomedical research and microelectronics device inspection. Some illustrative examples are presented. The quantitative methods described here are also very relevant to projection microscopy using other sources of radiation, such as visible light and electrons. [source] THOMAS REID ON MOLYNEUX'S QUESTIONPACIFIC PHILOSOPHICAL QUARTERLY, Issue 3 2005ROBERT HOPKINS The first version is used to address whether there are any properties originally perceived in both touch and vision. Although it is tempting to think the second discussion serves the same purpose, this would render pointless various novel features of the question Reid then frames. Instead, I suggest, Reid's second question provides the acid test of one of his central claims against the Ideal system, that the blind can form a conception of visible figure. The issue is not the cross-modality of perceptual representations, but the amodality of a central concept, as befits the Inquiry's central argumentative ambitions. [source] Heterogeneous transport costs and spatial sorting in a model of New Economic Geography,PAPERS IN REGIONAL SCIENCE, Issue 1 2010Corey Lang Economic geography; transport costs; sorting; agglomeration Abstract Transportation costs are of central importance in the New Economic Geography literature, though assumptions about transportation costs continue to be simplistic. This paper begins to address these simplifications by assuming that transportation costs for manufactured goods are heterogeneous. Basic results are consistent with standard models showing dispersion of economic activity for high transport costs and eventual agglomeration as transport costs decline. However, several novel features arise too. Many unstable, dispersed equilibria exist for high average transport costs, but converge to a stable equilibrium path as transport costs decrease. Equilibrium paths smoothly transition from dispersion to agglomeration and do so at an increasing rate. Additionally, transport costs directly influence firms' location decisions and firms spatially sort by transport cost. Resumen Los costos de transporte tienen una importancia capital en la literatura sobre la Nueva Geografía Económica, aunque se siguen asumiendo los costos de transporte de manera simplista. Este artículo empieza a tratar estas simplificaciones, asumiendo que los costos de transporte de bienes manufacturados son heterogéneos. Los resultados básicos son consecuentes con los modelos estándar que muestran la dispersión de la actividad económica para costos de transporte elevados y una eventual aglomeración a medida que los costos de transporte disminuyen. Sin embargo, también aparecen varias características novedosas. Existen muchos equilibrios dispersos, inestables, para costos de transporte promedio elevados, pero convergen en una línea de equilibrio a medida que los costos disminuyen. Las líneas de equilibrio tienen una transición fluida de la dispersión a la aglomeración y lo hacen a una tasa en aumento. Además, los costos de transporte influyen directamente las decisiones de localización de las empresas y estas se ordenan espacialmente de acuerdo a los costos de transporte. [source] The Ball,Berry,Leuning and Tardieu,Davies stomatal models: synthesis and extension within a spatially aggregated picture of guard cell functionPLANT CELL & ENVIRONMENT, Issue 11 2002R. C. Dewar Abstract A new model of stomatal conductance is proposed which combines the essential features of the Ball,Berry,Leuning (BBL) and Tardieu,Davies (TD) models within a simple spatially aggregated picture of guard cell function. The model thus provides a coherent description of stomatal responses to both air and soil environments. The model also presents some novel features not included in either the BBL or TD models: stomatal sensing of intercellular (rather than leaf surface) CO2 concentration; an explanation of all three observed regimes (A, B and C) of the stomatal response to air humidity (Monteith Plant, Cell and Environment 18, 357,364, 1995); incorporation of xylem embolism; and maintenance of hydraulic homeostasis by combined hydraulic and chemical signalling in leaves (in which leaf epidermal hydraulic conductivity plays a key role). Significantly, maintenance of hydraulic homeostasis in the model does not require a direct feedback signal from xylem embolism, the predicted minimum leaf water potential being independent of xylem hydraulic conductivity. It is suggested that stomatal regulation through combined hydraulic and chemical signalling in leaves and/or roots provides a general mechanism enabling plants to maintain their water potentials above a minimum value. Natural selection of the key stomatal parameters would then set the minimum potential to a specific value determined by the most vulnerable plant process under water stress (e.g. cell growth, protein synthesis or xylem cavitation), depending on species and growth conditions. [source] Recent work on entropically-driven ring-opening polymerizations: some potential applications,POLYMERS FOR ADVANCED TECHNOLOGIES, Issue 2-3 2005Philip Hodge Abstract The entropically-driven ring-opening polymerization of macrocyclic monomers (>ca. 14 ring atoms per repeat unit) and/or macrocyclic oligomers is a relatively new method of polymer synthesis that exploits the well-known phenomenon of ring-chain equilibria. It attracts interest because of its novel features. For example, these ring-opening polymerizations emit no volatiles and little or no heat. This review considers the principles of entropically-driven ring-opening polymerizations, gives selected examples and discusses potential applications. The latter include micromolding, high throughput syntheses and the synthesis of supramolecular polymers. Copyright © 2005 John Wiley & Sons, Ltd. [source] Response to novel food and the role of social influences in common marmosets (Callithrix jacchus) and Goeldi's monkeys (Callimico goeldii)AMERICAN JOURNAL OF PRIMATOLOGY, Issue 11 2007Elsa Addessi Abstract Neophobia, defined as showing caution toward novel features of the environment, is widespread in birds and mammals; it can be affected by ecology, early experience, and social context. In this study, we aimed to (i) investigate the response to novel food in adult common marmosets and Goeldi's monkeys and (ii) assess the role of social influences. We used an experimental paradigm employed previously with capuchin monkeys and children, in which a subject (observer) was presented with a novel food under three conditions: (i) Presence: group members did not have food; (ii) Different color: group members received familiar food whose color differed from that of the observer's novel food; (iii) Same color: group members received familiar food of the same color as the observer's novel food. Although most common marmosets tasted and/or ate the novel food, none of the Goeldi's monkeys ate it and only two sampled it. Differences in home range size and early social experience might explain the divergent behavior of the two species. Observers of both species similarly attended to group members and their visual attention increased with the number of group members eating, especially when the observer's and group members' foods were perceptually similar. However, we observed social influences on explorative behavior in Goeldi's monkeys but not on explorative or eating behavior in common marmosets. This result might be explained by the different pattern of response to novel food observed in the two species. Moreover, social influences on Goeldi's monkeys' behavior were nonspecific, i.e. they were not based on an appreciation that the food is safe because eaten by group members. Am. J. Primatol. 69:1210,1222, 2007. © 2007 Wiley-Liss, Inc. [source] | ||||||||||||||||||||||||||||